- Messages
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- Reaction score
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- Points
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Thank you so very much!Q16)
Take moments about the point X on the wall. You know that the weight lies in the middle, so if you assume the distance XY to be 1m (or 'x' m or whatever you want), the weight would be 0.5m from X. And the anti-clockwise moment, F is given by F sin 30 and it is 1m from X. So form an equation and solve:
F sin 30 * 1 = 0.5 * 10
F = 10.0 N
Q17) ..This one is kind of tricky, I think. I'm not sure if my method is correct. Check out the attachment. I basically found the angle between the strings Y and Z and then resolved forces to find the component 'x'. I did 4 cos 53.1 and then multiplied by 2 because there is a force acting both upwards and downwards. It turns out I got the right answer, but again, don't know if this is the proper method.
Q31) It can't be A because a +ve particle is going away from the +ve charge in the centre, so the repulsive force is decreasing.
It can definitely be B because that's basically the opposite of what I said above.
It can't be C or D because the force in an electric field is the same. In D, the +ve particle will experience the same force at any point. So the answer should be B.